The present invention relates to prosthetic devices adapted to be implanted between the vertebrae for treating degenerative or ruptured discs and for replacing damaged vertebral bodies. More particularly, the invention comprises a rigid vertebral body replacement cage which is annular in configuration and shaped for its particular application. The cages can be formed in a half-moon shape to be used in the center of the vertebral body, a modified kidney-shape to be used in the anterior portion of the vertebral body or of a smaller oval configuration for lateral applications on the sides of the vertebral body. The cages are configured to be used singularly or in stacked combination to replace a damaged disc and/or vertebrae and can also be secured inside the fibrous disc column connecting adjoining vertebrae to provide the necessary support in the spinal column.
While vertebral body replacement devices have been in use for several years, efforts have been ongoing to improve them. As a result of their configuration, the vertebral body replacement cages of the present invention are not only particularly well suited for their intended purpose, they are very versatile in their applications, easily placed into proper position during the operative procedure, whether used individually or in a stacked configuration and, when used in a stacked configuration, are far more easily joined together in a secure stack of desired length than those cages heretofore available. The result is a substantial improvement in vertebral body replacement devices.